Scottsdale, Ariz., attorney Craig Zirbel maintains there was a "Texas connection" in the Kennedy assassination.
PHOENIX -- LBJ did it.
He didn't pull the trigger, but he was in the thick of the conspiracy, according to a Scottsdale attorney who has written two books on the subject.
President John F. Kennedy was shot dead in Dallas 50 years ago Friday, and the attorney is certain that Lee Harvey Oswald's only involvement was as the fall guy.
MORE: Kennedy Assassination
On a recent morning, Craig Zirbel is sitting at a nondescript office in the Scottsdale Airpark, behind a desk that he says once belonged to Joseph McCarthy, the Wisconsin senator famous for his claims that Communists had infiltrated the government.
Zirbel has written two books on the Kennedy assassination, and, McCarthyesque government conspiracies aside, he says the public has but two choices on deciding what to believe about that November day: Either Lee Harvey Oswald, a man with no motive did it, or another theory must be devised.
A majority of people, according to polls, believe the conspiracy idea and have for a long time.
Zirbel delivers his conclusions with enthusiasm, waving his arms and raising his voice.
"I don't believe Oswald pulled the trigger," Zirbel says.
The attorney has been interested in the assassination for a long time.
Zirbel was in third grade when Kennedy was killed. He got a copy of the Warren Commission report on the assassination a year later, shortly after it was published. He says he did not understand much of it at the time, but he maintained his interest over the years.
The report, based on an investigation by a select government committee, concluded that Oswald acted alone in killing Kennedy. That has been the official finding ever since.
But that has not stopped conspiracy theories from persisting.
Zirbel has self-published two books on the subject, "The Texas Connection" in 1991 and "The Final Chapter on the Assassination of John F. Kennedy" in 2010. The titles have been well-received by some people, criticized by others — typical of the contentious and eccentric world of Kennedy conspiracy theorists.
One of them, political strategist Roger Stone, is the author of "The Man Who Killed Kennedy: The Case against LBJ," which came out this year.
"Craig Zirbel did some of the earliest and most important seminal work on LBJ's involvement in the murder of JFK," Stone said in an email. "I have used his book, 'The Texas Connection,' with attribution. I have tried to build on the solid foundation built by Zirbel."
Not all assassination buffs agree. It is easy to find numerous commentators who believe Zirbel misinterpreted some of the data.
The title of the book gives away Zirbel's position: that Vice President Lyndon B. Johnson and his associates in Texas were behind the assassination.
If Oswald did not pull the trigger — and Zirbel provides a list of reasons he believes he did not — then the explanation becomes more elusive.
Those who have interest in the case know the scenarios:
-- The Central Intelligence Agency, perhaps upset by changes in the agency that followed the failed Bay of Pigs invasion aimed at ousting Fidel Castro from leadership in Cuba.
-- The Mafia, arguably because of law-enforcement moves against organized crime by the Kennedy administration.
-- Anti-Castro Cuban exile groups, upset by the Bay of Pigs failure, perhaps working closely with the previous two groups.
-- Others, including the military industrial complex, a government agency such as the FBI, Southern segregationists, the Soviet Union or American conservatives.
Zirbel makes the case that Johnson, and only Johnson, had the motive, the means and the opportunity to mount a conspiracy against the president.
The motive: political gain. There were political differences, personal issues, Johnson's involvement in several scandals and his desire to become president before he got too old.
The opportunity: Kennedy's visit to LBJ's home turf in Texas. Johnson and his associates controlled many of the trip's details.
The means: shots by multiple gunmen firing from the direction of the now infamous grassy knoll. Hired perhaps by Johnson associates in the oil business, who had ties to the Mafia, Zirbel insists, there were at least two shooters.
He also emphasizes that as president, Johnson had the means to block any serious investigation.
And Oswald? His movements, his statements and his background make no sense if he was the lone gunman, Zirbel says. Even the site of the fatal shots was out of whack: Oswald would have had a much easier target several seconds earlier, as the motorcade slowed to turn twice, Zirbel notes.
It's the awkward turns, rather than the otherwise direct route the motorcade took, that strikes Zirbel.
"It's the thing that blows my mind away," he says. "It's the first time a route ever was changed from what the Secret Service had established."
The revised route took the motorcade directly past the Texas School Book Depository building and Dealey Plaza, site of the grassy knoll, from which many theorists believe the shots were fired.
Zirbel says John Connally, then Texas governor, had insisted upon the arrangement. Connally was an ally of Johnson. He, in fact, lost a fight over motorcade seating arrangements, was forced to ride with Kennedy and was wounded in the shooting.
Zirbel also points to statements by two known participants in his conspiracy: Oswald, who shouted, "I'm a patsy!" to nearby reporters at the Dallas jail, and Oswald's killer, Jack Ruby, who was quoted as saying, "If you knew the truth, you'd be amazed."
But it has been 50 years, and no conclusive evidence has emerged. Zirbel says the public is beginning to lose interest in the assassination. He says he never had interest in the "minutae," and is losing interest generally.
He has begun to sell off his assassination memorabilia, including his replica of the car the president was riding in that fateful day. Media calls have slowed down, too, bumping back up only because of the significance of the anniversary.
He still wants the public to see the case for what it is.
"All I want to get out," he says, "is that there was no lone assassin, and there was a conspiracy."
He and his like-minded investigators in the field have to be gratified with their efforts, although the numbers have slipped over the last decade.
According to a recent survey from the Associated Press, conducted in mid-April, 59 percent of Americans think multiple people were involved in a conspiracy to kill the president, while 24 percent think Oswald acted alone, and 16 percent are unsure. A 2003 Gallup poll found that 75 percent of Americans felt there was a conspiracy.
The Oswald-acted-alone results, meanwhile, are the highest since the period three years after the assassination, when 36 percent said one man was responsible for Kennedy's death.